What is the purging mechanism on historical tables during 80%

cylau · ‎08-17-2010

Hi,

I have a UCCE 7.2.5 environment. Lately the HDS database is reaching 80% usage threshold and the system started to purge the database automatically.

Realised the auto purge is always purging for a few tables only. Can someone advise how the auto purge works?

Appreciate your help in advanced.

Thanks.

regards,

khambetea · ‎08-17-2010

There are two purge settings in ICM -

Adjustment percentage - default 80%. Every night the database is purged to bring it below 80% usage.

Percent Full - Emergency purge - default 90% - at any time during the day or night, if the database is over 90% full, the purge will start and trim it down.

Hence the purge will not affect all tables equally. Not a good idea. It is better to have the database no more than 65-70 percent full so that the performance is optimal. You can expand the database using ICMDBA or Enterprise Manager.

The following link is a bit outdated but the info is still pretty ok.

http://www.cisco.com/en/US/products/sw/custcosw/ps1001/products_tech_note09186a008014f8b9.shtml

cylau · ‎08-17-2010

Hi,

Thanks for the info. I do understand the retention and purging settings. What I would like to find out is how this adjustment percentage work when the DB hits 80% usage. Is there a table index e.g. t_Call_Type_Half_Hour is 1 where everytime there is adjustment purging, this table will be the first to purge?

Thanks again.

regards,

joesnyde · ‎08-18-2010

Hi,

ICM purges at 12:30 (by default) each day whent the tables have reached 80%, this will continue until the data has become lower than 80%. No other purge will occur after this until the next day. If the database gets to 90% the purge will start at anytime and continue till it is below 80%. Both purge the oldest data in alphabetical order, i.e. the oldest Agent tables are purged first and then down the list.

Joe

cylau · ‎08-18-2010

Hi Joe,

Thanks for the info. You mentioned "purge the oldest data in alphabetical order", does it mean the following table order?

- t_Agent_Half_Hour: 615
- t_Agent_Logout: 2
- t_Agent_Skill_Group_Half_Hour: 615
- t_Agent_Skill_Group_Logout: 2
- t_Agent_State_Trace: 36
- t_Call_Type_Half_Hour: 10
- t_Network_Trunk_Group_Half_Hour: 780

- t_Peripheral_Half_Hour: 781

- t_Physical_Controller_Half_Hou: 781

- t_Route_Call_Detail: 1

- t_Route_Call_Variable: 1
- t_Route_Half_Hour: 781

- t_Routing_Client_Five_Minute: 781

- t_Service_Half_Hour: 781

- t_Skill_Group_Half_Hour: 781
- t_Termination_Call_Detail: 28

- t_Termination_Call_Variable: 1
- t_Trunk_Group_Half_Hour: 780

If you take a close look, the 615, 2, 36, 10 etc are actually the different day of data till date. For example, t_Call_Type_Half_Hour table has data upto 10 days only.

If the purge method mentioned earlier is true, the t_Agent_Half_Hour table should be the first to purge? But in real case, the purging tables are in random order.

Please advise.

Thanks.

regards,

khambetea · ‎08-18-2010

That has been my experience as well. What I have noticed is that within the operations, whatever table ICM is

updating at the moment when it reaches the 80% mark, it starts trimming from that table and onwards in an alphabetical pattern until the % full is below 80%. Hence the trimming is not even.

cylau · ‎08-18-2010

Hi,

The 80% adjustment purging happen at 12:30am. During that time, the contact center closed for the day. Hence, should not have agent logout, agent skill group logout and call type data writing to database.

With that, I see no reason that most of the trimming process happened on these tables. Please correct me if I am wrong.

Thanks.

geoff · ‎08-18-2010

I think purging is a bit of a mystery to all of us.

But Cisco do say the following (from the 2007 Networkers slides):

When you reach the > 80% threshold, the purge routine changes.
The normal purge occurs at 12:30am and the oldest day is purged from each table.
The 80% purge routine round robins through the tables alphabetically until space is less than 80%.
Loses Call detail before Half Hour.

Regards,

Geoff